Rack



FIG. 1 is a perspective view of the rack showing environmental structure that forms no part of the claimed sign in broken lines;

FIG. 2 is a front perspective view thereof;

FIG. 3 is a rear perspective view thereof;

FIG. 4 is a side view thereof;

FIG. 5 is a front view thereof;

FIG. 6 is a rear view thereof;

FIG. 7 is a top view thereof; and,

FIG. 8 is a bottom view thereof. The broken lines shown in FIGS. 2-8 are environmental and form no part of the claimed design. 

The ornamental design for a rack, as shown and described. 